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1.
Sci Adv ; 10(19): eado4489, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728391

RESUMO

Atropisomeric indoles defined by a N─N axis are an important class of heterocycles in synthetic and medicinal chemistry and material sciences. However, they remain heavily underexplored due to limited synthetic methods and challenging stereocontrol over the short N─N bonds. Here, we report highly atroposelective access to N─N axially chiral indoles via the asymmetric Larock reaction. This protocol leveraged the powerful role of chiral phosphoramidite ligand to attenuate the common ligand dissociation in the original Larock reaction, forming N─N chiral indoles with excellent functional group tolerance and high enantioselectivity via palladium-catalyzed intermolecular annulation between readily available o-iodoaniline and alkynes. The multifunctionality in the prepared chiral indoles allowed diverse post-coupling synthetic transformations, affording a broad array of functionalized chiral indoles. Experimental and computational studies have been conducted to explore the reaction mechanism, elucidating the enantio-determining and rate-limiting steps.

2.
RSC Adv ; 14(16): 11112-11120, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38590358

RESUMO

In recent years, finding high-performance energy storage materials has become a major challenge for Li-ion batteries. B-based two-dimensional materials have become the focus of attention because of their abundant reserves and non-toxic characteristics. A series of two-dimensional transition metal borides (MBenes) are reported and their electrochemical properties as anode materials for Li-ion batteries are investigated by density functional theory (DFT) calculations. The surface of MB2 possesses medium adsorption strength and diffusion energy barrier for Li atoms, which are conducive to the insertion and extraction of Li-ions during the charge/discharge process of Li-ion batteries. Herein, we explore the potential of MB2 (M = Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Cu and Zn) as the anode material for LIBs. Excitingly, the Li atom can be stably adsorbed on the surface of MB2 (M = Sc, Ti, V, Nb, Mo, W) monolayers, and the theoretical capacity of the MB2 monolayer is high (521.77-1610.20 mA h g-1). The average open circuit voltage range is within 0.10-1.00 V (vs. Li/Li+). The relationship between the p-band center of the B atom and the adsorption energy of Li on the surface of MB2 is also investigated. Furthermore, it is found that the charge transfer of Li atom and metallic center in the most stable position is strongly related to the corresponding value of diffusion energy barrier. These results confirm that MB2 monolayers are promising 2D anode materials for Li-ion batteries, demonstrating the application prospects of B-based 2D materials.

3.
Parasit Vectors ; 17(1): 178, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576040

RESUMO

BACKGROUND: To successfully replicate within the host cell, Toxoplasma gondii employs several mechanisms to overcome the host cell defenses and mitigate the harmful effects of the free radicals resulting from its own metabolic processes using effectors such as thioredoxin proteins. In this study, we characterize the location and functions of a newly identified thioredoxin in T. gondii, which was named Trx4. METHODS: We characterized the functional role of Trx4 in T. gondii Type I RH and Type II Pru strains by gene knockout and studied its subcellular localization by endogenous protein HA tagging using CRISPR-Cas9 gene editing. The enzyme-catalyzed proximity labeling technique, the TurboID system, was employed to identify the proteins in proximity to Trx4. RESULTS: Trx4 was identified as a dense granule protein of T. gondii predominantly expressed in the parasitophorous vacuole (PV) and was partially co-localized with GRA1 and GRA5. Functional analysis showed that deletion of trx4 markedly influenced the parasite lytic cycle, resulting in impaired host cell invasion capacity in both RH and Pru strains. Mutation of Trx domains in Trx4 in RH strain revealed that two Trx domains were important for the parasite invasion. By utilizing the TurboID system to biotinylate proteins in proximity to Trx4, we identified a substantial number of proteins, some of which are novel, and others are previously characterized, predominantly distributed in the dense granules. In addition, we uncovered three novel proteins co-localized with Trx4. Intriguingly, deletion of trx4 did not affect the localization of these three proteins. Finally, a virulence assay demonstrated that knockout of trx4 resulted in a significant attenuation of virulence and a significant reduction in brain cyst loads in mice. CONCLUSIONS: Trx4 plays an important role in T. gondii invasion and virulence in Type I RH strain and Type II Pru strain. Combining the TurboID system with CRISPR-Cas9 technique revealed many PV-localized proximity proteins associated with Trx4. These findings suggest a versatile role of Trx4 in mediating the processes that occur in this distinctive intracellular membrane-bound vacuolar compartment.


Assuntos
Toxoplasma , Animais , Camundongos , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Antígenos de Protozoários/genética , Virulência/genética , Fatores Imunológicos/metabolismo , Tiorredoxinas/genética
4.
World J Gastroenterol ; 30(1): 9-16, 2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38293326

RESUMO

In 2023, Baishideng Publishing Group (Baishideng) routinely published 47 open-access journals, including 46 English-language journals and 1 Chinese-language journal. Our successes were accomplished through the collective dedicated efforts of Baishideng staffs, Editorial Board Members, and Peer Reviewers. Among these 47 Baishideng journals, 7 are included in the Science Citation Index Expanded (SCIE) and 6 in the Emerging Sources Citation Index (ESCI). With the support of Baishideng authors, company staffs, Editorial Board Members, and Peer Reviewers, the publication work of 2023 is about to be successfully completed. This editorial summarizes the 2023 activities and accomplishments of the 13 SCIE- and ESCI-indexed Baishideng journals, outlines the Baishideng publishing policy changes and additions made this year, and highlights the unique advantages of Baishideng journals.


Assuntos
Publicações Periódicas como Assunto , Editoração , Humanos , Idioma
5.
J Colloid Interface Sci ; 659: 203-212, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38176230

RESUMO

Incorporating noble metal single atoms into lattice of spinel cobalt oxide (Co3O4) is an attractive way to fabricate oxygen evolution reaction (OER) electrocatalysts because of the high activity and economic benefit. The commonly used high valence noble metal dopants such as ruthenium, iridium and rhodium tend to supersede Co3+ at octahedral site of Co3O4 and result in great activity, the origins of admirable activity were also wildly investigated. However, bare explorations on doping noble metal single atom into tetrahedral site of Co3O4 to construct OER catalyst have been reported, corresponding catalytic activity and mechanism remain mystery. Here, a promising structure that tetrahedrally substituent Ag single atom embedded in Co3O4 nanoparticles on the surface of carbon nanotube (Ag-Co3O4/CNT) was presented, and its performance in OER was probed. The high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) and X-ray absorption spectroscopy (XAS) demonstrate the successful embeddedness of atomical Ag atom in Co3O4 lattice, the resultant electronic interaction is conducive to promote charge transfer for OER. Theoretical calculations further disclose that atomical Ag dopant prefers to replace tetrahedral Co2+ rather than octahedral Co3+. The substitution Ag acts as the active site through Ag-Co bridge and facilitates the desorption process, which improves the turnover frequency (TOF) and boosts the intrinsic activity of Ag-Co3O4/CNT. Benefiting from the essentials above, Ag-Co3O4/CNT displays remarkable activity (236 mV@10 mA cm-2) and robust stability for alkaline OER. This finding offers a potential direction for the design of noble metal single atom involved Co3O4 based OER electrocatalysts.

6.
Nat Commun ; 15(1): 793, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38278808

RESUMO

Sexual development in Toxoplasma gondii is a multistep process that culminates in the production of oocysts, constituting approximately 50% of human infections. However, the molecular mechanisms governing sexual commitment in this parasite remain poorly understood. Here, we demonstrate that the transcription factors AP2XI-2 and AP2XII-1 act as negative regulators, suppressing merozoite-primed pre-sexual commitment during asexual development. Depletion of AP2XI-2 in type II Pru strain induces merogony and production of mature merozoites in an alkaline medium but not in a neutral medium. In contrast, AP2XII-1-depleted Pru strain undergoes several rounds of merogony and produces merozoites in a neutral medium, with more pronounced effects observed under alkaline conditions. Additionally, we identified two additional AP2XI-2-interacting proteins involved in repressing merozoite programming. These findings underscore the intricate regulation of pre-sexual commitment by a network of factors and suggest that AP2XI-2 or AP2XII-1-depleted Pru parasites can serve as a model for studying merogony in vitro.


Assuntos
Toxoplasma , Animais , Humanos , Toxoplasma/metabolismo , Merozoítos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
7.
Int J Parasitol ; 54(2): 109-121, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37832712

RESUMO

Pathogenicity of the zoonotic pathogen Toxoplasma gondii largely depends on the secretion of effector proteins into the extracellular milieu and host cell cytosol, including the dense granule proteins (GRAs). The protein-encoding gene TGME49_299780 was previously identified as a contributor to parasite fitness. However, its involvement in parasite growth, virulence and infectivity in vitro and in vivo remains unknown. Here, we comprehensively examined the role of this new protein, termed GRA76, in parasite pathogenicity. Subcellular localization revealed high expression of GRA76 in tachyzoites inside the parasitophorous vacuole (PV). However, its expression was significantly decreased in bradyzoites. A CRISPR-Cas9 approach was used to knock out the gra76 gene in the T. gondii type I RH strain and type II Pru strain. The in vitro plaque assays and intracellular replication showed the involvement of GRA76 in replication of RH and Pru strains. Deletion of the gra76 gene significantly decreased parasite virulence, and reduced the brain cyst burden in mice. Using RNA sequencing, we detected a significant increase in the expression of bradyzoite-associated genes such as BAG1 and LDH2 in the PruΔgra76 strain compared with the wild-type Pru strain. Using an in vitro bradyzoite differentiation assay, we showed that loss of GRA76 significantly increased the propensity for parasites to form bradyzoites. Immunization with PruΔgra76 conferred partial protection against acute and chronic infection in mice. These findings show the important role of GRA76 in the pathogenesis of T. gondii and highlight the potential of PruΔgra76 as a candidate for a live-attenuated vaccine.


Assuntos
Toxoplasma , Animais , Camundongos , Toxoplasma/genética , Virulência/genética , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
8.
PLoS Pathog ; 19(12): e1011831, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38091362

RESUMO

Protein phosphatases are post-translational regulators of Toxoplasma gondii proliferation, tachyzoite-bradyzoite differentiation and pathogenesis. Here, we identify the putative protein phosphatase 6 (TgPP6) subunits of T. gondii and elucidate their role in the parasite lytic cycle. The putative catalytic subunit TgPP6C and regulatory subunit TgPP6R likely form a complex whereas the predicted structural subunit TgPP6S, with low homology to the human PP6 structural subunit, does not coassemble with TgPP6C and TgPP6R. Functional studies showed that TgPP6C and TgPP6R are essential for parasite growth and replication. The ablation of TgPP6C significantly reduced the synchronous division of the parasite's daughter cells during endodyogeny, resulting in disordered rosettes. Moreover, the six conserved motifs of TgPP6C were required for efficient endodyogeny. Phosphoproteomic analysis revealed that ablation of TgPP6C predominately altered the phosphorylation status of proteins involved in the regulation of the parasite cell cycle. Deletion of TgPP6C significantly attenuated the parasite virulence in mice. Immunization of mice with TgPP6C-deficient type I RH strain induced protective immunity against challenge with a lethal dose of RH or PYS tachyzoites and Pru cysts. Taken together, the results show that TgPP6C contributes to the cell division, replication and pathogenicity in T. gondii.


Assuntos
Parasitos , Fosfoproteínas Fosfatases , Toxoplasma , Animais , Humanos , Camundongos , Domínio Catalítico , Ciclo Celular/genética , Divisão Celular , Parasitos/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Toxoplasma/metabolismo , Virulência/genética , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo
9.
ISA Trans ; 143: 131-143, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37679272

RESUMO

When the autonomous vehicle (AV) is under various road friction and speed, emergency collision avoidance is extremely difficult. In this situation, the AV may encounter severe understeering problem, so it is hard to achieve collision avoidance, even under the control of active safety system. To tackle this problem, an adaptive collision avoidance strategy (ACAS) is proposed for AV under various road friction and speed. The adaptive performance of the ACAS is realized via three aspects. (1) An adaptive reference path planning method is proposed to provide desired evasive speed and reference path for the AV according to various road friction and reduces the turning burden of AV. (2) A predictive-based fuzzy controller is designed to realize the speed control, and it improves the tracking accuracy of various desired evasive speed. (3) A novel turning enhanced method built with a direct yaw turning controller and a torque distribution method can enhance the turning capability of AV. Finally, the proposed strategy is verified on AV via simulation experiments. The code can be found online here: https://github.com/wangjinlei-hnu/ACAS.

10.
11.
RSC Adv ; 13(34): 23409-23418, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37546216

RESUMO

The commercial application of surfaces with superhydrophilic (SHPL) properties is well known as an efficient strategy to address problems such as anti-fogging, anti-frosting, and anti-biological contamination. However, current SHPL coatings are limited by their poor water and abrasion resistances. Thus, herein, to solve these problems active glass was employed as a substrate, and a stable and transparent SHPL solution was prepared via the spraying process. Aqueous polyacrylic resin (PAA), SiO2 nanoparticles (NPs), tetraethyl orthosilicate (TEOS), and sodium allyl sulfonate (SDS) were utilized as the four main components of the PAA-TEOS-SiO2 coating. The durability properties including anti-abrasion, resistance to water, and contact component loss were investigated via the Taber abrasion test, boiling water immersion test, and anti-fogging test, respectively. Furthermore, the structure, composition, and wettability of the coating before and after the friction and water immersion tests were compared via water contact angle (WCA) measurements. Furthermore, the effect of the type of resin on the properties of the coating was investigated. The surface morphology of the blended water-based polyacrylic acid (PAA) resin was uniform and flat and its adhesion to the substrate was the highest (4.21 MPa). Considering the durability and optical properties of the coating, the optimal blend was 3 wt% PAA resin, which exhibited a transmittance of 90%. When the content of TEOS, which enhanced the crosslinking in the coating, was increased to 2 wt%, the results showed that the SHPL coating maintained good anti-friction, boiling resistance, and anti-fogging properties under the conditions of 300 cycle Taber friction with 250 g load and soaking in hot water at 100 °C for 1 h. In particular, the excellent durability of strong acid and alkali resistance, heat resistance, and long-term aging resistance will facilitate the commercial viability and expand the application of SHPL coating in various research fields.

12.
Medicine (Baltimore) ; 102(29): e34377, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37478220

RESUMO

Eosinophilic gastritis is characterized by gastrointestinal symptoms accompanied by peripheral eosinophilia. This study aims to explore the association between eosinophilic gastritis and Synaptosome Associated Protein 25 (SNAP25), and provide a new direction for the diagnosis and treatment of eosinophilic gastritis. GSE54043 was downloaded from the gene expression omnibus database. Differentially expressed genes (DEGs) were screened. The functions of common DEGs were annotated by Database for Annotation, Visualization and Integrated Discovery and Metascape. The protein-protein interaction network of common DEGs was obtained by Search Tool for the Retrieval of Interacting Genes and visualized by Cytoscape. Significant modules were identified from the protein-protein interaction network. A total of 186 patients with eosinophilic gastritis were recruited. The clinical data were recorded and the expression levels of CPE, SST, PCSK2, SNAP25, and SYT4 were detected. Pearson chi-square test and Spearman correlation coefficient were used to analyze the relationship between eosinophilic gastritis and related parameters. Univariate and multivariate Logistic regression were used for further analysis. 353 DEGs were presented. The top 10 genes screened by cytoHubb were shown, and Veen diagram figured out 5 mutual genes. Pearson's chi-square test showed that SNAP25 (P < .001) was significantly associated with eosinophilic gastritis. Spearman correlation coefficient showed a significant correlation between eosinophilic gastritis and SNAP25 (ρ = -0.569, P < .001). Univariate logistic regression analysis showed that SNAP25 (OR = 0.046, 95% CI: 0.018-0.116, P < .001) was significantly associated with eosinophilic gastritis. Multivariate logistic regression analysis showed that SNAP25 (OR = 0.024, 95% CI: 0.007-0.075, P < .001) was significantly associated with eosinophilic gastritis. The low expression of SNAP25 gene in eosinophilic gastritis is associated with a higher risk of eosinophilic gastritis.


Assuntos
Enterite , Eosinofilia , Humanos , Perfilação da Expressão Gênica , Mapas de Interação de Proteínas , Eosinofilia/genética , Proteína 25 Associada a Sinaptossoma/genética
13.
Alzheimers Dement ; 19(10): 4407-4420, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37493186

RESUMO

INTRODUCTION: Depression is considered a prodromal state of Alzheimer's disease (AD), yet the underlying mechanism(s) by which depression increases the risk of AD are not known. METHODS: Single-nucleotide polymorphism (SNP) analysis was used to determine the CALHM2 variants in AD patients. Cellular and molecular experiments were conducted to investigate the function of CALHM2 V136G mutation. We generated a new genetically engineered Calhm2 V136G mouse model and performed behavioral tests with these mice. RESULTS: CALHM2 V136G mutation (rs232660) is significantly associated with AD. V136G mutation resulted in loss of the CALHM2 ATP-release function in astrocytes and impaired synaptic plasticity. Mice homozygous for the Calhm2 V136G allele displayed depressive-like behaviors that were rescued by administration of exogenous ATP. Moreover, Calhm2 V136G mutation predisposed mice to cognitive decline in old age. DISCUSSION: CALHM2 dysfunction is a biologically relevant mechanism that may contribute to the observed clinical correlation between depression and AD.

14.
SLAS Discov ; 28(8): 385-393, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37399991

RESUMO

Tau tubulin kinase 1 (TTBK1) is a serine/threonine/tyrosine kinase that phosphorylates multiple residues in tau protein. Hyperphosphorylated tau is the main cause of tauopathy, such as Alzheimer's disease (AD). Therefore, preventing tau phosphorylation by inhibiting TTBK1 has been proposed as a therapeutic strategy for AD. However, few substrates of TTBK1 are reported for a biochemical assay and few inhibitors targeting TTBK1 have been reported so far. In this study, we identified a fluorescein amidite (FAM)-labeled peptide 15 from a small peptide library as the optimal peptide substrate for human TTBK1 (hTTBK1). We then developed and validated a microfluidics-based mobility shift assay (MMSA) with peptide 15. We further confirmed that peptide 15 could also be used in the ADP-Glo kinase assay. The established MMSA was applied for screening of a 427-compound kinase inhibitor library, yielding five compounds with IC50s of several micro molars against hTTBK1. Among them, three compounds, AZD5363, A-674,563 and GSK690693 inhibited hTTBK1 in an ATP competitive manner and molecular docking simulations revealed that they enter the ATP pocket and form one or two hydrogen bonds to the hinge region with hTTBK1. Another hit compound, piceatannol, showed non-ATP competitive inhibitory effect on hTTBK1 and may serve as a starting point to develop highly selective hTTBK1 inhibitors. Altogether, this study provided a new in vitro platform for the development of novel hTTBK1 inhibitors that might have potential applications in AD prevention.


Assuntos
Doença de Alzheimer , Microfluídica , Humanos , Ensaio de Desvio de Mobilidade Eletroforética , Simulação de Acoplamento Molecular , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Peptídeos , Trifosfato de Adenosina
15.
Membranes (Basel) ; 13(7)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37505003

RESUMO

Mine water cannot be directly consumed by trapped people when a mine collapses, so it is difficult for people to carry out emergency rescues to ensure their safety. Therefore, a water bag made of a forward osmosis (FO) membrane has been designed that can efficiently filter coal mine water to meet the urgent needs of emergency rescue. Before interfacial polymerization (IP), sodium-dodecyl-sulfate-modified halloysite (SDS-HNT) was added to an MPD aqueous solution to prepare an SDS-HNT polyamide active layer, and then the prepared membrane was placed into a polydopamine (PDA) solution formed by the self-polymerization of dopamine and a PDA/SDS-HNT composite film was prepared. The results showed that the original ridge-valley structure of the polyamide membrane was transformed to a rod-, circular-, and blade-like structure by the addition of SDS-HNTs. Subsequently, a dense PDA nanoparticle layer was formed on the modified membrane. The polyamide/polysulfone forward osmosis membrane modified by co-doping of PDA and SDS-HNTs displayed both the best water flux and rejection rate, confirming the synergistic effect of compound modification. Therefore, the high-performance permeability of the polyamide membrane modified by SDS-HNTs and PDA provides great convenience for the emergency filtration of coal mine water, and also has potential applications in wastewater treatment and seawater desalination.

16.
ACS Appl Mater Interfaces ; 15(31): 37143-37156, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37498789

RESUMO

Ferroptosis holds great potential in cancer treatment, but its efficacy is severely limited by a low Fenton reaction efficacy. Meanwhile, the interactive relationship between Ferroptosis and the PD-1 blockade is still vague. Herein, a hydrazide/Cu/Fe/indocyanine green coordinated nanoplatform (TCFI) is constructed by a hydrazide-metal-sulfonate coordination process. The TCFI nanoplatform exhibits Fenton-/catalase-/glutathione oxidase-like triple activities and accordingly can trigger lipid peroxidation, relieve hypoxia, and downregulate the glutathione/glutathione peroxidase 4 axis, thus achieving positively and negatively dually enhanced Ferroptosis in B16F10 cancer cells. Under near-infrared laser irradiation, the TCFI nanoplatform induces robust immunogenic cancer cell death by elevating the intracellular reactive oxygen species level through synergistic photodynamic therapy/Ferroptosis, which significantly potentiates CD8+ T cell infiltration into tumors and interferon-γ secretion. Moreover, upregulated interferon-γ efficiently inhibits system xc- activity and sensitizes cancer cells to Ferroptosis. Interestingly, the PD-1 blockade may strengthen the reciprocal process. The combination of the TCFI nanoplatform and αPD-1 can eliminate primary tumors and inhibit distant tumor growth, lung metastasis, and tumor recurrence. This study presents a simple and novel coordination strategy to fabricate tumor microenvironment-responsive nanodrugs and highlights the enhancement effect of photodynamic therapy on reciprocal Ferroptosis and antitumor immunity.


Assuntos
Ferroptose , Melanoma , Neoplasias , Humanos , Verde de Indocianina , Interferon gama , Receptor de Morte Celular Programada 1 , Hidrazinas , Raios Infravermelhos , Linhagem Celular Tumoral , Microambiente Tumoral
17.
Int J Nanomedicine ; 18: 3339-3358, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37361387

RESUMO

Background: Bacterial invasion, protracted inflammation, and angiogenesis inhibition are hallmarks of chronic diabetic wounds, bringing about patient morbidity and rising healthcare costs. For such wounds, there are currently few efficient therapies available. Methods: We reported the development of carboxymethyl chitosan (CMCS)-based self-healing hydrogel loaded with ultra-small copper nanoparticles (Cunps) for local treatment of diabetic wound healing. The structure of Cunps was identified by XRD, TEM, XPS and other methods, and the characterization of the synthesized Cunps-loaded self-healing carboxymethyl chitosan (CMCS)-protocatechualdehyde (PCA) hydrogel (Cunps@CMCS-PCA hydrogel) was further investigated. The therapeutic effect of Cunps@CMCS-PCA hydrogel in diabetic wound healing was explored in vitro and in vivo. Results: The findings showed that a kind of ultra-small size copper nanoparticles with excellent biocompatibility was prepared. CMCS was chemically conjugated to PCA to form self-healing hydrogels via the formation of an amide bond followed by the loading of ultra-small copper nanoparticles. The obtained Cunps@CMCS-PCA hydrogel showed a typical three-dimensional interlinked network structure with self-healing ability and porosity. It exhibited good biocompatibility in diabetic wounds. Furthermore, Cunps@CMCS-PCA hydrogel group significantly prevented bacterial growth in the skin wound of diabetic rats as compared to model group and CMCS-PCA hydrogel-treated group. After 3 days, no visible bacterial proliferation was observed. It also increased angiogenesis through Cunps mediated activation of ATP7A to prevent induction of autophagy. Furthermore, Cunps@CMCS-PCA hydrogel mainly depended on PCA-induced inhibition on inflammation of macrophage via JAK2/STAT3 signaling pathway. As a result, compared with delayed wound healing process with lower wound healing rate valued at 68.6% within 7 days in the model group, Cunps@CMCS-PCA significantly accelerated wound healing recovery and increased wound healing rate to 86.5%, suggesting that Cunps@CMCS-PCA hydrogel effectively accelerated wound healing. Conclusion: Cunps@CMCS-PCA hydrogel offered a new therapeutic approach for quickening diabetic wound healing.


Assuntos
Quitosana , Diabetes Mellitus Experimental , Nanopartículas , Ratos , Animais , Hidrogéis/química , Cobre/farmacologia , Quitosana/química , Diabetes Mellitus Experimental/tratamento farmacológico , Cicatrização , Antibacterianos/farmacologia , Antibacterianos/química
18.
FASEB J ; 37(6): e22932, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37115746

RESUMO

Glutaredoxins (Grxs) are ubiquitous antioxidant proteins involved in many molecular processes to protect cells against oxidative damage. Here, we study the roles of Grxs in the pathogenicity of Toxoplasma gondii. We show that Grxs are localized in the mitochondria (Grx1), cytoplasm (Grx2), and apicoplast (Grx3, Grx4), while Grx5 had an undetectable level of expression. We generated Δgrx1-5 mutants of T. gondii type I RH and type II Pru strains using CRISPR-Cas9 system. No significant differences in the infectivity were detected between four Δgrx (grx2-grx5) strains and their respective wild-type (WT) strains in vitro or in vivo. Additionally, no differences were detected in the production of reactive oxygen species, total antioxidant capacity, superoxide dismutase activity, and sensitivity to external oxidative stimuli. Interestingly, RHΔgrx1 or PruΔgrx1 exhibited significant differences in all the investigated aspects compared to the other grx2-grx5 mutant and WT strains. Transcriptome analysis suggests that deletion of grx1 altered the expression of genes involved in transport and metabolic pathways, signal transduction, translation, and obsolete oxidation-reduction process. The data support the conclusion that grx1 supports T. gondii resistance to oxidative killing and is essential for the parasite growth in cultured cells and pathogenicity in mice and that the active site CGFS motif was necessary for Grx1 activity.


Assuntos
Antioxidantes , Toxoplasma , Animais , Camundongos , Glutarredoxinas/genética , Toxoplasma/genética , Sequência de Aminoácidos , Virulência , Oxirredução , Estresse Oxidativo
19.
J Colloid Interface Sci ; 642: 255-263, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37004259

RESUMO

Superhydrophilic coatings have incomparable advantages in anti-fogging and self-cleaning but are limited to poor abrasion resistance and water resistance. Consequently, the research on the contradiction between hydrophilicity and water resistance, as well as abrasion resistance and visible transmittance, has become a focus of superhydrophilic coatings. Herein, we design a ceramic-polymer superhydrophilic composite coating with a high density, strong cross-linking structure, and smooth surface. Because of its static water contact angle (WCA = 3.2°) and short water spreading time (ST = 1878 ms), the transparent composite coating exhibits anti-fogging performance. Meanwhile, it exhibits anti-fogging durability even after 400 Taber abrasion cycles under a 250 g load or immersion in boiling water for 30 min. Furthermore, the result of self-cleaning characterization and theoretical analysis demonstrate that the low surface roughness endows the composite coating with excellent self-cleaning properties. The composite coating can effectively scavenge oil and dust pollution on its surface in a humid environment. Thus, the developed composite coating in this work is potential in the anti-fogging and self-cleaning fields.

20.
Adv Healthc Mater ; 12(13): e2202949, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36716523

RESUMO

Cuproptosis is a recently discovered form of programmed cell death and shows great potential in cancer treatment. Herein, a copper-dithiocarbamate chelate-doped and artemisinin-loaded hollow nanoplatform (HNP) is developed via a chelation competition-induced hollowing strategy for cuproptosis-based combination therapy. The HNP exhibits tumor microenvironment-triggered catalytic activity, wherein liberated Cu2+ catalyzes artemisinin and endogenous H2 O2 to produce C-centered radicals and hydroxyl radicals, respectively. Meanwhile, the disulfide bonds-rich HNP can deplete intracellular glutathione, thus triply amplifying tumor oxidative stress. The augmented oxidative stress sensitizes cancer cells to the cuproptosis, causing prominent dihydrolipoamide S-acetyltransferase oligomerization and mitochondrial dysfunction. Moreover, the HNP can activate ferroptosis via inhibiting GPX4 activity and trigger apoptosis via dithiocarbamate-copper chelate-mediated ubiquitinated proteins accumulation, resulting in potent antitumor efficacy. Such a cuproptosis/ferroptosis/apoptosis synergetic strategy opens a new avenue for cancer therapy.


Assuntos
Apoptose , Artemisininas , Neoplasias , Linhagem Celular Tumoral , Terapia Combinada , Cobre/farmacologia , Neoplasias/tratamento farmacológico , Estresse Oxidativo , Microambiente Tumoral
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